// TODO 循环队列: 1. 使用size实现  2. 不使用size实现
public class LoopQueue<E> implements Queue<E>{

    private E[] data;
    private int head, tail;
    private int size;

    public LoopQueue(int capacity) {
        data = (E[]) new Object[capacity];
        head = tail = size = 0;
    }

    public LoopQueue() { this(10); }

    @Override
    public void enqueue(E e) {

    }

    @Override
    public E dequeue() {
        return null;
    }

    @Override
    public E front() {
        return null;
    }

    @Override
    public boolean isEmpty() {
        return false;
    }

    @Override
    public int size() {
        return 0;
    }
}
